<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style type="text/css">
    .tab ul {
      overflow: hidden;
      padding: 0;
      margin: 0;
    }

    .tab ul li {
      box-sizing: border-box;
      padding: 0;
      float: left;
      width: 100px;
      height: 45px;
      line-height: 45px;
      list-style: none;
      text-align: center;
      border-top: 1px solid blue;
      border-right: 1px solid blue;

    }

    .tab ul li {
      border-left: 1px solid blue;
    }

    .tab ul li.active {
      background-color: orange;
    }

    .tab div {
      width: 500px;
      height: 300px;
      display: none;
      text-align: center;
      font-size: 30px;
      line-height: 300px;
      border: 1px solid blue;
      border-top: 0px;
    }

    .tab div.current {
      display: block;
    }
  </style>
</head>

<body>
  <div id="app">
    <div class="tab">
      <ul>
        <li @click='change(index)' :class="currentIndex === index ? 'active' : '' " v-for='(item,index) in list'
          :key='item.id'>{{item.title}}</li>
        <!-- :class='currentIndex === index ? 'active' : ''' 对比点击的索引是否一样，如果一样就使用active类，高亮 -->
      </ul>
      <div :class="currentIndex === index ? 'current' : ''" v-for='(item,index) in list' :key='index'><img
          :src='item.img' :alt='item.title'></div>
      <!-- :class='currentIndex === index ? 'current' : ''' 对比点击的索引是否一样，如果一样就使用current类，对应图片显示 不再隐藏 -->
    </div>
  </div>
  <script src="../vue.js"></script>
  <script>
    var vm = new Vue({
      el: '#app',
      data: {
        currentIndex: 0,
        list: [
          {
            id: 1,
            title: '苹果',
            img: './images/apple.png'
          }, {
            id: 2,
            title: '橘子',
            img: './images/orange.png'
          }, {
            id: 3,
            title: '柠檬',
            img: './images/lemon.png'
          }
        ]
      },
      methods: {
        change(index) {
          this.currentIndex = index
        }
      }
    })
  </script>
</body>

</html>